Lulu Garcia-Navarro: Mayor Zohran Mamdani of New York City is riding high. In an era when the public is sour on politics, recent polls show him actually becoming more popular among New Yorkers. It’s fair to say that some of that is vibes: As the Knicks won the N.B.A. championship, Mamdani became one of the team’s main hype men, basking in the reflected glow of their victory; the World Cup has been a raging success with New York City awash with celebrating fans; Taylor Swift got married in a secret celebration in the most visible of New York venues.

As his star rises, Mamdani, a democratic socialist, has also been flexing his political power in new ways — his endorsement of three progressive candidates for the House of Representatives gave them the edge against establishment-backed incumbents and contenders, and cemented his role as a kingmaker in the Democratic Party. Mamdani, of course, also has many detractors, on the right but also among Democratic leaders in Washington who worry about his influence and his aims in pulling the party further to the left.

I sat down with Mamdani earlier this week to talk about what has turned out to be a fascinating, and controversial, experiment in what democratic socialist governance can do in America’s most important capitalist city.